1. Field of the Invention
The present invention relates to an apparatus for forcibly bending a foot about a foot joint of an inferior limb of a living person, while pressing a sole (planta pedis) of the foot, thereby preventing foot-drop (talipes equinus) and deep venous thrombosis.
2. Related Art Statement
A patient who has been ill in bed for a long time is likely to suffer foot-drop, i.e., the disease that foot joint cannot be bent from its stretched position. Some patients suffer this disease in two weeks only. A patient who suffers foot-drop cannot easily walk and needs a long time to achieve rehabilitation. Thus, it is strongly desirable to prevent foot-drop. Foot-drop can be prevented by sometimes bending the foot. However, many patients who suffer foot-drop cannot bend their feet without help, because of, e.g., paralysis of peroneal nerve.
There has been developed no apparatus for preventing foot-drop, and there has been proposed only a training apparatus for restoring the function of a foot suffering foot-drop. For example, Japanese Patent Document No. 9-253144 discloses a function-restoring training apparatus. This training apparatus includes an air bag which is provided in vicinity of an ankle on the side of an instep (dorsum pedis); a support band which has a shape of loop, is wound around a portion of a lower leg located between the ankle and the knee, is connected at one end thereof to the air bag, and fixes the air bag to the ankle; and a tension band which has a shape of loop, is wound around a portion of a sole located between toes and a heel, and is connected at one end thereof to an upper surface of the air bag. When the air bag is charged with air and the air is discharged from the air bag, the air bag pulls, and loosens, the tension band, thereby forcibly bending the foot about the foot joint.
It is speculated that if a patient uses the above-indicated function-restoring apparatus before he or she suffers foot-drop, he or she can prevent the disease. On the other hand, a patient who has been ill in bed for a long time is likely to suffer deep venous thrombosis (DVT), i.e., the disease that blood clots develop and float in veins of an inferior limb, and even clog the veins, because his or her blood is likely to stay in the veins. This disease is accelerated if the patient has the problem of abnormal coagulation or dehydration, and may develop in from several hours to one day.
There has been proposed an apparatus for preventing the above-indicated deep venous thrombosis. This apparatus includes a support belt which supports an air bag and is worn on a foot of a living person such that the air bag is positioned on the sole of the foot and so that the air bag is supplied with pressurized air and is inflated to press the sole. When a living person walks, venous blood is pumped up from the veins of the sole of foot by the pressure caused by load, and is conveyed from the inferior limb to the heart. However, a patient who has been ill in bed for a long time is short of the pressure applied to his or her sole and accordingly is likely to suffer venous thrombosis. Hence, if the above-indicated apparatus is used to press the sole, deep venous thrombosis can be prevented. However, the apparatus that can only press sole cannot prevent foot-drop.
Thus, according to the conventional art, both a foot-drop preventing apparatus and a deep-venous-thrombosis preventing apparatus must be used to prevent foot-drop and deep venous thrombosis. That is, first, a patient wears the foot-drop preventing apparatus on his or her foot, performs a prescribed operation to prevent foot-drop, then puts the apparatus off the foot, subsequently wears the deep-venous-thrombosis preventing apparatus on the foot, and then performs a prescribed operation to prevent deep venous thrombosis. These actions are very cumbersome and time-consuming.
It is therefore an object of the present invention to provide an apparatus for simultaneously preventing foot-drop and deep venous thrombosis.
The above object has been achieved by the present invention. According to a first feature of the present invention, there is provided an apparatus for bending and stretching a foot of a living person by pressing at least an arch of a sole of the foot and stopping the pressing of the arch.
According to this feature, while at least the arch of the foot is pressed, the foot is bent; and when the pressing of the arch is stopped, the foot is naturally returned to its stretched state. When these actions are repeated, the bending and stretching of the foot are repeated. Thus, the foot is prevented from foot-drop. In addition, since at least the arch of the foot is pressed while the foot is bent, the foot is prevented from deep venous thrombosis.
According to a second feature of the present invention, there is provided an apparatus for bending and stretching a foot of a living person, comprising a pressurized-gas supplying device which supplies a pressurized gas; and an inflatable bag which is provided in vicinity of an arch of a sole of the foot, and is inflated by the pressurized gas supplied by the pressurized-gas supplying device, so as to press at least the arch of the sole of the foot.
According to this feature, when the inflatable bag is inflated by the pressurized gas supplied by the pressurized-gas supplying device, the inflated bag presses at least the arch of the sole, thereby bending the foot. When the inflation of the bag is stopped, the pressing of the sole is also stopped, so that the foot is naturally returned to its stretched state. Since the foot can be iteratively bent and stretched by repeating these actions, the foot can be prevented from foot-drop. In addition, since at least the arch of the foot is pressed while the foot is bent, the foot is prevented from deep venous thrombosis.
According to a third feature of the present invention, there is provided an apparatus for bending and stretching a foot of a living person, comprising a support plate including a base portion which is adapted to be worn on a lower portion of an inferior limb of the person such that the base portion is not movable relative to the inferior limb, and an end portion which is inclined relative to the base portion in a direction away from the foot of the inferior limb and is opposed to an instep of the foot; an inflatable bag which is provided on one of opposite sides of the end portion of the support plate that is opposite to the instep; a pressurized-gas supplying device which supplies a pressurized gas to the inflatable bag; a pressing member which is provided in vicinity of an arch of a sole of the foot; and a binding member which binds the end portion of the support plate, the inflatable bag, and the pressing member, around the foot, such that the bag is inflatable by the pressurized gas supplied by the pressurized-gas supplying device.
According to this feature, the binding member binds the end portion of the support plate, the inflatable bag, and the pressing member, around the foot. Therefore, if the bag is inflated inside the binding member, the pressing member presses at least the arch of the sole and simultaneously the pressing member and the foot are moved toward the end portion of the support plate. In addition, since the base portion of the support plate is fixed to the lower leg and the end portion thereof is inclined relative to the base portion in a direction away from the foot, the foot is bent when the inflatable bag is inflated and the foot is moved toward the end portion. Moreover, when the inflation of the bag is stopped, the pressing member also stops pressing the sole, so that the foot is naturally returned to its stretched state. Since the foot can be iteratively bent and stretched by repeating these actions, the foot can be prevented from foot-drop. In addition, since at least the arch of the foot is pressed while the foot is bent, the foot is prevented from deep venous thrombosis.
According to a fourth feature of the present invention, there is provided an apparatus for bending and stretching a foot of a living person, comprising an inflatable bag which is opposed to an instep of the foot and a shin of a lower portion of an inferior limb of the person, the inflatable bag including a first portion which is opposed to the instep and is deformed, when the bag is inflated, to form a curved portion, the inflatable bag additionally including a second portion which is opposed to the lower portion and is worn on the lower portion such that the second portion is not movable relative to the lower portion; a pressurized-gas supplying device which supplies a pressurized gas to the inflatable bag; a pressing member which is provided in vicinity of a sole of the foot; and a connecting member which connects the inflatable bag and the pressing member to each other such that a distance between the inflatable bag and the pressing member is substantially unchangeable.
According to this feature, a portion of the inflatable bag is opposed, and fixed, to the lower leg, and the distance between the inflatable bag and the pressing member is kept unchanged by the connecting member. Therefore, when the inflatable bag is inflated and accordingly a portion of the bag that is opposed to the instep is deformed to form a curved portion, the pressing member is moved toward the sole to press the sole and thereby bend the foot. Meanwhile, when the inflation of the bag is stopped, the pressing member also stops pressing the sole, so that the foot is naturally returned to its stretched state. Since the foot can be iteratively bent and stretched by repeating these actions, the foot can be prevented from foot-drop. In addition, since at least the arch of the foot is pressed while the foot is bent, the foot is prevented from deep venous thrombosis.
According to a fifth feature of the present invention, there is provided an apparatus for bending and stretching a foot of a living person, comprising a bending device including an elongate flexible plate and a bellows tube held in close contact with the flexible tube, the bellows tube being opposed to an instep of the foot, one of lengthwise opposite end portions of the bending device being worn on a shin of a lower portion of an inferior limb of the person such that the one end portion of the bending device is not movable relative to the lower portion; a pressurized-gas supplying device which supplies a pressurized gas to the bellows tube of the bending device; a pressing member which is provided in vicinity of a sole of the foot; and a connecting member which connects the bending device and the pressing member to each other such that a distance between the bending device and the pressing member is substantially unchangeable.
According to this feature, when the bellows tube is supplied with the pressurized gas and is inflated, the flexible plate is so curved that the curved flexible plate is located inside the inflated bellows tube. Since one of lengthwise opposite end portions of the bending device is fixed to the shin of the lower leg, a portion of the bending device that is opposed to the instep is curved in a direction away from the instep, when the bending device is curved. In addition, since the distance between the bending device and the pressing member is kept unchanged by the connecting member. Therefore, when the bending device is curved in a direction away from the instep, the pressing member presses the sole and thereby bends the foot. Meanwhile, when the pressurized gas is discharged from the bellows tube, the pressing member also stops pressing the sole, so that the foot is naturally returned to its stretched state. Since the foot can be iteratively bent and stretched by repeating these actions, the foot can be prevented from foot-drop. In addition, since at least the arch of the foot is pressed while the foot is bent, the foot is prevented from deep venous thrombosis.
According to a sixth feature of the present invention, the foot bending and stretching apparatus further comprises an annular inflatable bag which is adapted to support a heel of the foot, the annular bag being inflated to lift the heel off a floor.
When the annular bag of this foot bending and stretching apparatus is inflated, the heel is lifted off the floor. When the heel is sometimes lifted off the floor, the foot can be prevented from bedsore.